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1
2 package org.apache.commons.el.parser;
3
4
8
9 public final class SimpleCharStream
10 {
11 public static final boolean staticFlag = false;
12 int bufsize;
13 int available;
14 int tokenBegin;
15 public int bufpos = -1;
16 private int bufline[];
17 private int bufcolumn[];
18
19 private int column = 0;
20 private int line = 1;
21
22 private boolean prevCharIsCR = false;
23 private boolean prevCharIsLF = false;
24
25 private java.io.Reader  inputStream;
26
27 private char[] buffer;
28 private int maxNextCharInd = 0;
29 private int inBuf = 0;
30
31 private final void ExpandBuff(boolean wrapAround)
32 {
33 char[] newbuffer = new char[bufsize + 2048];
34 int newbufline[] = new int[bufsize + 2048];
35 int newbufcolumn[] = new int[bufsize + 2048];
36
37 try
38 {
39 if (wrapAround)
40 {
41 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
42 System.arraycopy(buffer, 0, newbuffer,
43 bufsize - tokenBegin, bufpos);
44 buffer = newbuffer;
45
46 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
47 System.arraycopy(bufline, 0, newbufline, bufsize - tokenBegin, bufpos);
48 bufline = newbufline;
49
50 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
51 System.arraycopy(bufcolumn, 0, newbufcolumn, bufsize - tokenBegin, bufpos);
52 bufcolumn = newbufcolumn;
53
54 maxNextCharInd = (bufpos += (bufsize - tokenBegin));
55 }
56 else
57 {
58 System.arraycopy(buffer, tokenBegin, newbuffer, 0, bufsize - tokenBegin);
59 buffer = newbuffer;
60
61 System.arraycopy(bufline, tokenBegin, newbufline, 0, bufsize - tokenBegin);
62 bufline = newbufline;
63
64 System.arraycopy(bufcolumn, tokenBegin, newbufcolumn, 0, bufsize - tokenBegin);
65 bufcolumn = newbufcolumn;
66
67 maxNextCharInd = (bufpos -= tokenBegin);
68 }
69 }
70 catch (Throwable t)
71 {
72 throw new Error (t.getMessage());
73 }
74
75
76 bufsize += 2048;
77 available = bufsize;
78 tokenBegin = 0;
79 }
80
81 private final void FillBuff() throws java.io.IOException
82 {
83 if (maxNextCharInd == available)
84 {
85 if (available == bufsize)
86 {
87 if (tokenBegin > 2048)
88 {
89 bufpos = maxNextCharInd = 0;
90 available = tokenBegin;
91 }
92 else if (tokenBegin < 0)
93 bufpos = maxNextCharInd = 0;
94 else
95 ExpandBuff(false);
96 }
97 else if (available > tokenBegin)
98 available = bufsize;
99 else if ((tokenBegin - available) < 2048)
100 ExpandBuff(true);
101 else
102 available = tokenBegin;
103 }
104
105 int i;
106 try {
107 if ((i = inputStream.read(buffer, maxNextCharInd,
108 available - maxNextCharInd)) == -1)
109 {
110 inputStream.close();
111 throw new java.io.IOException ();
112 }
113 else
114 maxNextCharInd += i;
115 return;
116 }
117 catch(java.io.IOException e) {
118 --bufpos;
119 backup(0);
120 if (tokenBegin == -1)
121 tokenBegin = bufpos;
122 throw e;
123 }
124 }
125
126 public final char BeginToken() throws java.io.IOException
127 {
128 tokenBegin = -1;
129 char c = readChar();
130 tokenBegin = bufpos;
131
132 return c;
133 }
134
135 private final void UpdateLineColumn(char c)
136 {
137 column++;
138
139 if (prevCharIsLF)
140 {
141 prevCharIsLF = false;
142 line += (column = 1);
143 }
144 else if (prevCharIsCR)
145 {
146 prevCharIsCR = false;
147 if (c == '\n')
148 {
149 prevCharIsLF = true;
150 }
151 else
152 line += (column = 1);
153 }
154
155 switch (c)
156 {
157 case '\r' :
158 prevCharIsCR = true;
159 break;
160 case '\n' :
161 prevCharIsLF = true;
162 break;
163 case '\t' :
164 column--;
165 column += (8 - (column & 07));
166 break;
167 default :
168 break;
169 }
170
171 bufline[bufpos] = line;
172 bufcolumn[bufpos] = column;
173 }
174
175 public final char readChar() throws java.io.IOException
176 {
177 if (inBuf > 0)
178 {
179 --inBuf;
180
181 if (++bufpos == bufsize)
182 bufpos = 0;
183
184 return buffer[bufpos];
185 }
186
187 if (++bufpos >= maxNextCharInd)
188 FillBuff();
189
190 char c = buffer[bufpos];
191
192 UpdateLineColumn(c);
193 return (c);
194 }
195
196
200
201 public final int getColumn() {
202 return bufcolumn[bufpos];
203 }
204
205
209
210 public final int getLine() {
211 return bufline[bufpos];
212 }
213
214 public final int getEndColumn() {
215 return bufcolumn[bufpos];
216 }
217
218 public final int getEndLine() {
219 return bufline[bufpos];
220 }
221
222 public final int getBeginColumn() {
223 return bufcolumn[tokenBegin];
224 }
225
226 public final int getBeginLine() {
227 return bufline[tokenBegin];
228 }
229
230 public final void backup(int amount) {
231
232 inBuf += amount;
233 if ((bufpos -= amount) < 0)
234 bufpos += bufsize;
235 }
236
237 public SimpleCharStream(java.io.Reader dstream, int startline,
238 int startcolumn, int buffersize)
239 {
240 inputStream = dstream;
241 line = startline;
242 column = startcolumn - 1;
243
244 available = bufsize = buffersize;
245 buffer = new char[buffersize];
246 bufline = new int[buffersize];
247 bufcolumn = new int[buffersize];
248 }
249
250 public SimpleCharStream(java.io.Reader dstream, int startline,
251 int startcolumn)
252 {
253 this(dstream, startline, startcolumn, 4096);
254 }
255
256 public SimpleCharStream(java.io.Reader dstream)
257 {
258 this(dstream, 1, 1, 4096);
259 }
260 public void ReInit(java.io.Reader dstream, int startline,
261 int startcolumn, int buffersize)
262 {
263 inputStream = dstream;
264 line = startline;
265 column = startcolumn - 1;
266
267 if (buffer == null || buffersize != buffer.length)
268 {
269 available = bufsize = buffersize;
270 buffer = new char[buffersize];
271 bufline = new int[buffersize];
272 bufcolumn = new int[buffersize];
273 }
274 prevCharIsLF = prevCharIsCR = false;
275 tokenBegin = inBuf = maxNextCharInd = 0;
276 bufpos = -1;
277 }
278
279 public void ReInit(java.io.Reader dstream, int startline,
280 int startcolumn)
281 {
282 ReInit(dstream, startline, startcolumn, 4096);
283 }
284
285 public void ReInit(java.io.Reader dstream)
286 {
287 ReInit(dstream, 1, 1, 4096);
288 }
289 public SimpleCharStream(java.io.InputStream dstream, int startline,
290 int startcolumn, int buffersize)
291 {
292 this(new java.io.InputStreamReader (dstream), startline, startcolumn, 4096);
293 }
294
295 public SimpleCharStream(java.io.InputStream dstream, int startline,
296 int startcolumn)
297 {
298 this(dstream, startline, startcolumn, 4096);
299 }
300
301 public SimpleCharStream(java.io.InputStream dstream)
302 {
303 this(dstream, 1, 1, 4096);
304 }
305
306 public void ReInit(java.io.InputStream dstream, int startline,
307 int startcolumn, int buffersize)
308 {
309 ReInit(new java.io.InputStreamReader (dstream), startline, startcolumn, 4096);
310 }
311
312 public void ReInit(java.io.InputStream dstream)
313 {
314 ReInit(dstream, 1, 1, 4096);
315 }
316 public void ReInit(java.io.InputStream dstream, int startline,
317 int startcolumn)
318 {
319 ReInit(dstream, startline, startcolumn, 4096);
320 }
321 public final String GetImage()
322 {
323 if (bufpos >= tokenBegin)
324 return new String (buffer, tokenBegin, bufpos - tokenBegin + 1);
325 else
326 return new String (buffer, tokenBegin, bufsize - tokenBegin) +
327 new String (buffer, 0, bufpos + 1);
328 }
329
330 public final char[] GetSuffix(int len)
331 {
332 char[] ret = new char[len];
333
334 if ((bufpos + 1) >= len)
335 System.arraycopy(buffer, bufpos - len + 1, ret, 0, len);
336 else
337 {
338 System.arraycopy(buffer, bufsize - (len - bufpos - 1), ret, 0,
339 len - bufpos - 1);
340 System.arraycopy(buffer, 0, ret, len - bufpos - 1, bufpos + 1);
341 }
342
343 return ret;
344 }
345
346 public void Done()
347 {
348 buffer = null;
349 bufline = null;
350 bufcolumn = null;
351 }
352
353
356 public void adjustBeginLineColumn(int newLine, int newCol)
357 {
358 int start = tokenBegin;
359 int len;
360
361 if (bufpos >= tokenBegin)
362 {
363 len = bufpos - tokenBegin + inBuf + 1;
364 }
365 else
366 {
367 len = bufsize - tokenBegin + bufpos + 1 + inBuf;
368 }
369
370 int i = 0, j = 0, k = 0;
371 int nextColDiff = 0, columnDiff = 0;
372
373 while (i < len &&
374 bufline[j = start % bufsize] == bufline[k = ++start % bufsize])
375 {
376 bufline[j] = newLine;
377 nextColDiff = columnDiff + bufcolumn[k] - bufcolumn[j];
378 bufcolumn[j] = newCol + columnDiff;
379 columnDiff = nextColDiff;
380 i++;
381 }
382
383 if (i < len)
384 {
385 bufline[j] = newLine++;
386 bufcolumn[j] = newCol + columnDiff;
387
388 while (i++ < len)
389 {
390 if (bufline[j = start % bufsize] != bufline[++start % bufsize])
391 bufline[j] = newLine++;
392 else
393 bufline[j] = newLine;
394 }
395 }
396
397 line = bufline[j];
398 column = bufcolumn[j];
399 }
400
401 }
402 |
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